1. Field of the Invention
This invention relates to the masking of circuit boards for wave soldering. In particular, the invention relates to the masking of circuit boards, and to the use of a mask, such that the leads of leaded components are exposed for soldering while surface mounted components are masked from the solder.
Circuit boards often have components mounted on both surfaces, and such components may be a mix of leaded components and surface mounted components. It therefore occurs that on a particular surface of a circuit board there will be surface mounted components soldered to the circuit pattern on that surface, and also the ends of leads extending through the board from components on the other surface, which ends are also to be soldered to the circuit pattern on the particular surface.
2. Related Art
Conventionally, the surface mount components are positioned first and soldered to the circuit pattern, as by reflow soldering. The board is then turned over and leaded components mounted by their leads being inserted into and through the board. The leads are then connected to the circuit pattern. Ideally, this would be done on an automated soldering line, by wave soldering. However, the presence of the surface mounted components creates problems.